Attention, unattached men: There is hope. You don't need six-pack abs, an amazing job, or even an unsullied hairline to snag that beautiful girl you've been eyeing. Flab and a complete absence of self-esteem can be potent aphrodisiacs, as is proven by the patron saint of those heretofore undesirable qualities who's cavorting about the state of the Longacre and getting more action than the hottest Hollywood star.

His name is Robert Lambert, and as played by the sterling Mark Rylance in the iffy new revival of Marc Camoletti's Boeing-Boeing, he dispenses gallons of sparkling reassurance to world's schlubbiest singles. It might just be the ordinary guy's fantasy that a Wisconsin-born-and-bred loser could transform from an underdog into a raging pit bull, shedding a shoulder-rolling slouch in favor of the saucier swivel of bumps and grinds inspired by the three stunning women he meets. But in Rylance's hands, the dream is as convincing as it is delightful.

You believe with him, as you might not when you look in the mirror, that a man who's barely employed, has no prospects or fashion sense, and is never the subject of even a woman's second or third glance can morph into a border-hopping lothario. Robert is, above all, smart, and it's a short leap from devising a dozen different excuses to keep one suspicious fiancée out of the room in which another is hiding to (literally) charming the pants off yet another he's attempting to divert for, well, similar reasons.

Because of Rylance's gold-buffed improvisational attitude, this master juggler's talents aren't revealed until the moment they're required. Rylance so embraces Robert's desperation, not merely to survive the one libidinous day in which he's trapped but to thrive on the many curvaceous opportunities it presents, that there are times you can't help but wonder whether there any boundaries this newly born superman won't cross in pursuit of fulfillment, love, and sex (though not necessarily in that order).

With the rest of Matthew Warchus's production, which uses Beverley Cross and Francis Evans's adaptation, you'll wonder why anyone else is even there. The farther Rylance gets from center stage, the closer the show comes to stalling in midair.

Like most farces, this one is fragile and difficult, subject to the subtle whims of timing and intention that everyday comedy may occasionally shun - a lark for the audience, a vulture for the actors. Because most of the rest of the cast is committed to things other than the specific problems facing their characters, they seem inhabitants of isolated pockets of hilarity rather than the steady stream of pseudo-violent absurdity it can be at its best.

In fact, this is one of the rare cases where the setup stomps the execution. The life of American businessman Bernard (Bradley Whitford) is one of orchestrated chaos, derived from rotating his three serious girlfriends in and out of his luxurious Paris apartment (the gleaming-cream work of Rob Howell). Because they're flight attendants for competing airlines, all he must do is plan his life around their immutable schedules and he can do whatever - and whomever - he chooses when the numbers are in perfect alignment.

Christine Baranski and Mary McCormackPhoto by Joan Marcus.

His semi-willing accomplice is his catty maid Berthe (Christine Baranski), who strips the apartment of telltale traces between visits. And both do a good job of it - each of the cheerful American Gloria (Kathryn Hahn), the doting Italian Gabriella (Gina Gershon), and the dominating German Gretchen (Mary McCormack) believes she's the only woman in Bernard's life.

Warchus applies gentle heat to the first act's simmering pandemonium, building to giddy heights the suspense about how the women's departure and arrival schedules will tangle themselves to bring about what Bernard considers impossible: all three in his apartment at the same time. But when they collide there, with Bernard so flustered and overparted that it falls to the milquetoast Robert to pick up the pieces, all but Rylance's portion of that promise is left unfulfilled.

Gershon and McCormack are obsessed with their vocal performances, differentiating themselves with Saturday Night Live accents that alone aren't enough to establish the urgent personalities each woman needs. McCormack's guttural bellows, while unquestionably funny, lack the substantive undercurrents of laissez-faire romanticism that would conceivably send her from Bernard's arms into Robert's. Gershon is somewhat more natural, but doesn't capture the settle-down spirit that should power Gabrielle's choices.

Looking like a stripper slumming as a secretary, Baranski is all wiry neuroticism and not the stern taskmaster needed to force Bernard into line; her only modest projection and French-fried accent make her as difficult to hear as she is to understand, let alone comprehend. Whitford is the human equivalent of a live wire, flailing about and shrieking as though to exist is to surge, but channels little of the on-the-precipice excitement that should both elevate Bernard and give him so very far to fall. It's impossible to imagine their two energies coexisting long enough to concoct Bernard's daring scheme, let alone last five minutes without strangling each other.

Hahn's deceptive sunniness grants Gloria a few extra layers of richness that locate her much closer to Rylance's camp. A tightly coiffed example of the with-it ditz, she's as unafraid as Robert to shed her preconceptions, and Hahn makes her every bit as unpredictable. The scenes in which Robert and Gloria vamp each other, with looks, hands, or mouths, are the most charged and rewarding of the evening. Hahn's wordless flash of a towel and Rylance's priceless reaction to it is as close as this Boeing-Boeing gets to a comic one-two punch.

But if you must settle for a single uppercut, Rylance is the knock-out. Bernard's explanation of his complicated four-way arrangement illuminates Robert's shadowy attic, and watching Rylance spend over two hours clearing out the cobwebs from his unlived celebrates the kind of honest joy found in far too few of this season's Broadway comedies.

Robert may have no confidence in his ability to get what he wants, but he's unafraid to go after it, at any personal cost - a reminder that a night of a thousand kisses begins with a single peck on the cheek. Only when the wallflower joins the dance and learns he can't stop grooving to the music does he - and, for that matter, Boeing-Boeing - truly take off.